stream micro-interrumptions

[TheOldPresbyope]

@officialsm

I just deleted my first reply. It was a "ready-fire-aim" post that missed the mark. Sorry.

Your system appears to be having USB communications issues.

First steps to troubleshoot:

• ensure an adequate power supply, power cable, connector
  
• disconnect all USB devices except the DAC (CXA 81 == a Cambridge Audio amp?)
  
• try different USB cables and be sure to remove any extraneous inline gear such as hub or conditioner
  
• (out of an overabundance of caution, try different USB ports on the RPi)
  

After rebooting there should be nothing in the syslog but lines like these (for my USB Khadas Tone Board)

Code:

Feb 22 08:08:04 moode kernel: [    1.993593] usb 1-1.4: new high-speed USB device number 3 using xhci_hcd
...
Feb 22 08:08:04 moode kernel: [    2.134138] usb 1-1.4: New USB device found, idVendor=3353, idProduct=a001, bcdDevice= 2.00
Feb 22 08:08:04 moode kernel: [    2.136147] usb 1-1.4: New USB device strings: Mfr=1, Product=3, SerialNumber=0
Feb 22 08:08:04 moode kernel: [    2.138237] usb 1-1.4: Product: Tone1
Feb 22 08:08:04 moode kernel: [    2.139290] usb 1-1.4: Manufacturer: Khadas

That "unsupported format" line in your syslog is emitted by a low-level ALSA routine but I don't care to conjecture about it. Better to ask your DAC vendor.
The usb 1-1.5 messages in the syslog suggest a problem with your pen drive. Probably better just copying a track or two to your uSD card for test purposes.

Regards,
Kent

PS - don't forget the first rule of requesting support: give a complete accounting of the hardware setup including make/model of all items. Same goes for software.